// BAD get(target, prop) { return target[prop]; // Ignores proxy inheritance } // GOOD get(target, prop, receiver) { return Reflect.get(target, prop, receiver); // Maintains correct this } Sometimes you need a proxy made with reflect that can be revoked. Use Proxy.revocable .
function createLoggingProxy(target, name = "Object") { return new Proxy(target, { get(target, prop, receiver) { const value = Reflect.get(target, prop, receiver); console.log(`[${name}] GET ${String(prop)} → ${value}`); return typeof value === 'function' ? value.bind(target) // Preserve context for methods : value; }, set(target, prop, value, receiver) { console.log(`[${name}] SET ${String(prop)} = ${value}`); return Reflect.set(target, prop, value, receiver); } }); } const user = { name: "Alice", age: 30 }; const monitoredUser = createLoggingProxy(user, "User"); monitoredUser.age = 31; // Logs: [User] SET age = 31 console.log(monitoredUser.name); // Logs: [User] GET name → Alice proxy made with reflect 4 top
function createTransparentProxy(target) { return new Proxy(target, { get(target, prop, receiver) { return Reflect.get(target, prop, receiver); }, set(target, prop, value, receiver) { return Reflect.set(target, prop, value, receiver); }, has(target, prop) { return Reflect.has(target, prop); }, deleteProperty(target, prop) { return Reflect.deleteProperty(target, prop); }, apply(target, thisArg, argumentsList) { return Reflect.apply(target, thisArg, argumentsList); }, construct(target, argumentsList, newTarget) { return Reflect.construct(target, argumentsList, newTarget); } }); } Using Reflect ensures that if the target object has native getters or inherits from a prototype, the proxy respects those behaviors without additional code. One of the "top" use cases is logging without breaking the application logic. // BAD get(target, prop) { return target[prop]; //
: It uses Reflect to capture the exact value, including getters that might compute results dynamically. 3. Validation Proxy (Top Security) A common requirement is to validate data before allowing mutations. This pattern powers libraries like Vuex and MobX. age: 30 }